I would loosen the line at the wheel cylinder and pump, see if it gets wet(seriously no perversion intended Ha) before condemning the wheel cylinders. You could do this without help. Fluid goes in and comes out, getting blocked at some point. Process of elimination. look at it in sections.
Master
Lines to front distribution block,
Line
Rear distribution block
Line split to wheels
Wheel cylinders left and right
You could loosen the lines one at a time either from front to back or back to front
